Life on the mudflats

At first glance, the Wadden Sea appears barren and lifeless with its vast expanses of bare sand. But beneath the surface is a veritable myriad of life that plays a crucial role in the entire Wadden Sea ecosystem.

At first glance, the wading surface does not seem to hold much life - but it does...

In the mudflats, the treasure is buried

The mudflats are full of both algae and benthic animals. And while it may not be a treasure trove of gold, it is a veritable treasure trove of food for birds and fish. Compared to the average seabed, the mudflat contains ten times more animals by weight. With a total area of 4,700 square kilometres, this makes the mudflats a gigantic pantry. The conditions for the rich wildlife are created in particular by the tides, which bring nutrient-rich water into the shallow Wadden Sea twice a day. The basis for life is the high abundance of microscopic algae, especially diatoms, which form the first link in the food chain. Diatoms live floating in the water, on the surface of the mudflats and down in the mudflats. It is also the diatoms that give the mudflats their brown colour. In just 1 cm2, there can be up to 2.5 million diatoms, which are the primary food source for benthic animals such as sandworms, snails and small crustaceans. The bottom dwellers in turn become food for birds and other larger animals.

The right mix

The rich life in the mudflats is dependent on the right mix of sand and clay - the so-called candy. The largest number of animals live in places where the mud makes up up to a fifth of the bottom. If the bottom is pure sand or pure mud, there are only a few animals. Most of the animals in the wadden are quite small, but they often appear in staggering numbers. There can be over 100 roundworms in just one cubic centimetre of mudflat. Living on top of the wadding is the dune snail, which measures just a few millimetres and is therefore easily overlooked. But they are extremely numerous: in just one square metre, there can be up to 120,000 snails.

Experience the wadden sea

There are great opportunities to get up close and personal with the life of the wadden. And there is something for every taste and temperament. If you are up for it, you can easily explore on your own. If you want to dig up mussels, it is a good idea to bring a grab - it makes it a little easier. You can also take the kids with you and let them walk around the mudflats in bare feet, so they can really feel the lick between their toes. It is exciting to explore the hidden life of the mudflat, but as it is not safe to go far out on the mudflat, it is a good idea to be well prepared to avoid unpleasant surprises. It is therefore advisable to plan your trip based on the tide forecast and decide in advance when you will return. You can also book a guided tour with one of our partners - a knowledgeable guide will take you out on the water and make sure you have a great experience.

The characteristic small piles of sand bear witness to the sand worm's activity below the surface

Read more about the microscopic wildlife of the mudflats

Boy fishing for horse prawns. In some restaurants in the area, it is served as mudflat prawns

How to be the best guest when exploring the mudflats

  • We prepare at home and have checked the tide table at DMI ( so that we don't get caught in high tide while on the wadden sea
  • We never go out in fog and always bring a compass and mobile phone so we can find our way in case of sudden sea spray or fog.
  • We remember that we are guests in nature and avoid disturbing birds, seals and other animals.
  • We pick up any rubbish we find and take it with us - even if it's not our own.

Fotos: Petra Grundmann, Lars Maltha Rasmussen